Electric contact apparatus



2 Sheets-Sheet 1. A J. P. B. PTSKB. ELECTRIC CONTACT APPARATUS.

Patented July 11,1893.

(No Model.)

(No Model.) 2 Sheets-Sheet 2.

' J. P. B. PISKP..

ELECTRIC CONTACT APPARATUS.

No. 501,206. Patented July 11, 1893.

UNITED STATES PATENT OEEICE.

JONATHAN I. B. FISKE, OF LYNN, MASSACHUSETTS, ASSIGNOR TO THE THOMSON-HOUSTON ELECTRIC COMPANY, OF CONNECTICUT.

ELECTRIC CONTACT APPARATUS.

SPECIFICATION forming part of Letters Patent No. 501,206, dated July 11, 1893.

Application filed August 12I 1891. Serial No. 102,416. (No model.)

To all whom it may concern,.-

Be it known that I, JONATHAN P. B. FIsKE, a citizen of the United States, residing at Lynn, in the county of Essex and State of l\Iassachusetts,have invented certain new and useful Improvements in Electric Contact Apparatus, of which the following is a specification.

This invention relates to improvements in electric contact apparatus, such as are used to govern electric currents employed for varions purposes, as in the stoppingand starting of electric motors, the governing of the speed of such motors, duc.

The object of the invention is to make a switch or controller which is easily repaired, and to this end the contact plates are made to be individually removable or capable of being removed in groups of two or three, whereby these parts of the controller may be replaced when they become Worn, or if they prove to be defective, while the controller is in position, thus effecting a saving of time and expense.

In the accompanying drawings, Figure l is a sectional view and Fig. 2 is a plan of one form of the invention. Fig. 3 is a diagram of the circuit connections. Figs. 4 and 5 show a modified form.

In Fig.1,E, E are cast metal boxes of similar form secured to and arranged at a proper distance apart upon the base piece A, with their contact supporting portions facing each other in such manner that a brush carrier may pass between the contact plates on the opposite sides. The contact segments or plates are embraced or clamped between anges or shoulders o, on said boxes, and clamps,followers or blocks D,which are forced and held toward and against the segments by screws s2, s3, and the blocks may be locked in their advanced or final position by any suitable locking arrangement, such as screws s, which press upon the blocks D, laterally. The segments S, S, in the drawings are shown as having Wedge-shaped ends, the part or shoulder o of the casing or box E and the block D being correspondingly V-shaped, wedgen shaped or undercut to engage the ends of the segments or Contact plates, but it is evident that the contour of these parts might be modified in many ways without altering the principle of the construction. Insulation I, separates the segments from one another and from the casing and blocks. The segments or contact plates S are provided wit-l1 ears e from which connections may be made to resistances used 'to govern an electric circuit, or such connections may lead to any circuits which it is desired to control. The movable portion of the controller is operated by a handle Il and consists of brushes C, which are preferably made of two or more blocks of carbon, carried by a box B and pressed against the contact plates S by intermediate springs TV, which press against the inner ends of the brushes but are out of electrical connection therewith, a piece of insulation IA1 Fig. 2 being inserted for this purpose. The spring is insulatedin this manner to prevent its carrying current which might heat it and destroy its temper. Guides ff, Fig. l, are provided for the brush carrier. The connections from the ears e, of the plates S may be made to different points in a resistance coil as indicated in Fig. 3 at 1, 2, 3, dre., and it will be seen that a movement of the brushes C in the direction of the arrow cuts out resistance on both sides, the arrangement being such that such resistn ances are cutout and in, in series.

The modification shown in Figs. 4. and is adapted for use in a controller in which the contact plates or segments are arranged in a circle, and the brushes are carried upon an arm adapted to traverse these plates by its rotation about a center effected by a pinion P attached thereto meshing with the rack It carried by a suitable handle. The segments S, Fig. 5, have projections which enter def pressions in the cast ring D', the contour of the engaging surfaces being made to correspond approximately. Insulation I, as in the case of the other construction referred to, is placed between the plates S and the ring D',

and this insulation is by preference made of a number of thin sheets of mica built up to a suitable thickness over a' form corresponding to the shape of the metal surfaces to which it is to be applied. Wvhen the contact plates, and insulation are in position the following block D is forced against the insulation and plate by turning the screw s2, which binds the plate firmlyin position. The screw s2 may be tted with a locking device of any convenient kind to lock it in its ultimate p0- sition. The segments having all been placed in position in a circle as shown in Fig. 4, they are planed off in the manufacturing, but when a single segment is inserted in making repairs or replacements it can be tiled to a surface in a plane with the adjacent plates.

What I claim as new, and desire to secure by Letters Patent, is

l. In an electrical contact apparatus, the combination of a base or support, a series of contact pieces a series of followers or blocks bearing against said contact pieces, and a series of individually adjustable clamping or holding devices for such blocks.

2. In an electrical contact apparatus, the combination with a series of contact pieces provided with wedge shaped bearings of a base and a series of individually adjustable clamping devices, engaging with the contact pieces by such wedge-shaped bearings.

3. The combination of the base having an undercut shoulder, the series of contacts bearing against such shoulder and the series of individually adjustable clamping devices for such contacts.

4. The combination of the metal base having an undercut or wedge-formed bearing portion or shoulder, a series of contacts, a series of individually adjustable clamping devices holding such contacts against said shoulder, and insulation interposed between the contacts and the base, shoulder and clamping devices.

5. The combination of the base, the series of individually removable contacts, the series of followers, the individual adjusting screws therefor having locking devices.

6. An electrical contact apparatus comprising two parallel boxes, two series of separately removable insulated contacts carried by and secured to said boxes by separate clamping devices and facing one another, two electrically united brushes bearing respectively against said two series of contacts and electrical circuit connections leading from said two series of contacts. 7. An electrical contactapparatus comprising two parallel series of contacts, two brushes bearing against the inner faces of such contacts, and springs provided with insulation interposed between such brushes and forcing them apart.

8. The combination of the base, the parallel side boxes, two series of insulated contacts on the inner sides thereof, the two brushes bearing against said series of contacts, and a carrier for said brushes guided in said boxes.

In witness whereof I have hereunto set my hand this 5th day of August, 1891.

JONATHAN I). B. FISKE.

Witnesses:

JOHN W. GIBBONEY, BENJAMIN B. HULL. 

